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A. H. LYMN AND N. E. RAMBUSH.

RECOVERY 0F AMMONIA FROM PRODUCERIGS.

APFLCTlON FILED .IULY 2311918.

Pacensed July 8, 1919 @www5 2 SHEETS-SHEET l.

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fe/6 5. Rambus y A. H. LYMN ANU N. E. HAMBUSH.

REcovERY of Mmmm mom. PRODUCER GAS.

APPLICATION FILED JULY 23. i98.

inne of water, it is impossible to prevent the water from retaining a considerable amount ot' ammonia, on account ot' the solubility of ammonia. in water. At ordinary temperature 1050 parts of ammonia are soluble in parts ot' water and even at 100o C. 97 volumes ot' ammonia remain dissolved in 100 parts of water. The ammonia, which is therefore necessarily retained in the cooling water, would be lost for recovery.

The present invention aims at overcoming the aforemeiitioneddrawbacks and provides an economical ammonia recovery producer gas process and apparatus whereby a clean ammonium -saltI maybe produced and an economical process calried out even when using such acids as are unstable zit-thc teinperatures ot' the usual process.

According to this invention the steam and tar are simultaneously condensed and separated from the gas inone operation while the ammonia remains in thegas so, that practically all the ammonia leaving the gas producer will be conta-ined in the cleaned gas which is then absorbed by washing it with an acid 1n the cold. y

For this purpose the gas is passed through -condensing means acting on a principle similar to retllix condeiisers. Said conl densmg means are kept near the. zone where y,

the gas enters at a temperature just at or above the dew point e. not materially below 80 (l. (if necessary b v additional means) so that ammonia which may have been absorbed by the condensate is continuously volatilized, whereas near the zone where the gas leaves. the temperature is kept at such a degree not, materially above 40 C. that the steam and tar are condensed While the ammonia passes away with the gases.

Additional means may be provided for volatilizing any small amount of ammonia that may not have been completely volatilized from the condensate prior to its flowing from the reflux condenserg such as cfor instance heating the condensate with or witliout the addition ofliine or other alkali.

Means are also provided toutilize the heat of the gases which is communicated to' the cooling water, for pur-heating the air ot' the-producer blast. l

In the following one way of carrying out the invention is given by way of example:

Thehot products leaving the producer are passed in a' known manner through a gas washer wherein the dust contained inthe gases is removed in al wet state and in which the gases are cooled down toa Atemperature not materially lower than about 80 C. ln order to recover any fixed anin'ionia, (ammonium sulfate, ammonium chlorid, ete.,) which may be dissolved in the washing liquid some lime may be introduced into the Washer in a known manner. Instead ot' passing the gases tothe ammonia absorber as is usuallv done. according to the present invention the gases .are passed upwrd through a tubular or other suitable confienscr, or through a plurality ot such condensers arranged in series or in parallel, actinpr on a principle. similar to retin); condensers wherein the steam and tarare condensed from the gas practically without. absorption ot' ammonia. These condensers are however worked differently troni the way in which condensers are usually worked in so t'ar as we keep the condenser near the zone 4where the gas enters` at a temperature which is just at or above the deiv point i'. c. not materially below S00 C. (if necessary by outside means) so that ammonia which may have been absorbed by the condensate is continuously volatilized, whereas near the zone of said condenser where the gas leaves, the temperature is kept at such a degree not materially above 400 C. that the steam and tar are condensed, while the aiiiiiiouia passes away with the gases. rlfhe tar and practically all the moisture are thus removed from the gas simultaneously and in one operation except that amount of moisture which corresponds to the dew point of the cooled gas leaving the condensers, 'i'. e. the amount ot' moisture necessary to saturate the gas at the temperature at which it. leaves the condenser.

By this ineanstlie steam contained in the gas entering' for example at the' lowest part..

ot' a vertical condenser on rising condenses and naturally more and more ammonia will be absorbed as the gases ascend. This condensate falling down the condenser together with the condensed. tar comes into contact with the hotter regions below and thus again gives oft' the absorbed ammonia, while the condensed steam itself will not .be materially va-porized owing to the fact that the gas is maintained at its dewpoint. Any ammonia remaining in the hot condensate may be driven o by any suitable means and returned to the gas entering the condenser. Part of the condensate leaving the condensers may be used as make up water in the dust washer.

As apparatus tor carrying out this process a number ot' superimposed tubular condensers may be used: Between the tube plate of each two tubular comlensers a free space may be provided for airing the gases and vapors passing through. the tubes. The gas passes upward tl as the space ontsir the tubes is fed with cooling Water.

In order to recover the heat communicated by the gas to the cooling water and to saturate theuair, the air blast on its way to the producer may be passed through the spaces between the tubes' i. e. around the tubes through which the gas passes. The cooling water bein supplied in the form of liquid .nigh the tubes where-- nlms surrounding seid tribes inside which the gas passes, the nir einst on its wey to the producer thus cornes ini@ .intimate Contact with the Water ilnis resniting in an eiiicienc as l cri e general airproducer nc in which of the narcotics is `used.

sho n sectional cievntion of the irs-,cris used i eferring to Fi? l duce?? or ges gsi is ges generzred is conducted through conduit o to e. dust-separator c. iinter errying out the process. o indi stes 'the pro- 2e is circnieied gn 'this cirirsepnrsor through the in e d issues '5min the outc inllo is grises reed troni nirities eers 'the t ust- ned enter described and ter sind issue through one pipe in.: s steam pipe heineA prf, l ,E

f y snnnonin tit i nn'i'n'ionin ol Ay? end enter the siniere nrnniorie is nhpessingf c nitric soiniion or the hire "m solution, (eni- 'ii-cid or en scid ssh 'hrongh the n..

lil@ nionnin'i nist-nts 'or einer nnnnonnnn ssl.) .issues freni the pipe e and is coiiected in g2, whence it een wcroorcd for crys'niiisstion. Y e aninioniai Essi-'es i; sorher through the pipe g find may he ed consumed or L' ges holder in 'i1-e nsnsi manner. fr is :in inici through 'wh cirnir., on its wey to the produc hlsst, is .ssed with the object, of utiiizing the nest d eoinmunicned to the cooling Water e condenser The. het air issues from condenser through 'the 3 enters the producer hlns.

Referring non* 2j fthev condenser for ehe steine end es comprising n r '1 r concienscr of superimposed ents z5, if?, t3, I of e. ninnes if, (u to if) pistes.

r rh reference to l enfer' g,

passing through che cubes u of the oettoin compartment, enter e space e, in which their temperature is eqnnlized'. From seid specs o, 'she poss through the second tubular condenser t. from which they issue The into the space r' nrrnnged hetn'cen the second condenser i' and the third condenser fr. The gases continue to ascend through the successive tuhes und compartments zin'd iinnlly issue through the pipe Z.

Cold vanter is admitted in the opposite direction io the gigas, entering the top condenser t hrongh the pipe ce, into the distributing chamber ci, which uniformlyv distributes the waiter :ind cnnses i to descend the outer surface of the condenser tubes if. From the top condenser i5, the writer passes through n plurality of vertical pipes arranged centrally ot' which only one. 1/. is shown, into the distributing' chinnher or the second tuhn hir condenser :ind leaves this condenser through :i plurality of vertical outlet pipes y entering the distributing clnunher on the top of 'the third tubular condenser t, :md beingr` finally discharged 'through the pipe Additional water iniety pipes fw :ind we to condenser t4' and 3 are provided, the object of these being to regulate the temperature neer the top et the condenser.

The iower part, of the eoinlenser is siinilnrly arranged, waiter is admitted to the condenser compartment fig through the pipe w3 :ind passes through the outlet pipe y into the distributing compartment on the top of ihe condenser t@ leaving seid condenser through the outlet pipe 1/1 nnd entering the disrihntine' compari-ment on the top o5" the condenser t, the hol' water heiner linnll;y dischnrcfed from the condenser through' the pipe ic.

No ndditioinil wner inlets have heen shown :it Aiie three lower condenser compartnieni/s. hei-:inse the temperature is sutiiciently controlled by the VIneens provided in the 'zipper portion. ri`he nir blastr` on its wey to the. prothicere is passed through the tuhe r the tuhular condenser f3, end this :iir 'blast comes into intimate Contact, with the water lro surrounding' tubes u?, which resuits in en `efticient heut interchange and saturation of the hlns't. The nir leaves the tuhnlnr condenser t2 through the pipe 1" and enters thc top of the tubular condenser iV where e siinihir heat interchange is efxnonia contained in the precincts leaving the producer, remains in the cooled cleaned gas leaving the condenser. This gas ma),Y be passed through centrifugal or other tarseparators to remove the last traces of tar, and thence directly into an ammonia absorber and neutralized in the cold With any acid, including the unstable acids, and acid salt solutions.

What we claim as new and desire to secure by Letters Patent of `the United States 1s:-

l. In the recovery of ammonia from producer gas subjecting an ascending current of producer gas prior to the removal of amlnonia to temperatures progressively diminishing from not materially below 80 C. to not materially above 40 C. in a manner compelling the condensate to gravitate through the region of highest temperature.

2. In the recovery of ammonia from producer gas passing an ascending current of producer gas prior to the removal of ammonia in a plurality of streams in contact with extrancously cooled surfaces in such way that the gas is subjected to progressively diminishing temperatures from not materially below 80O C. at'the gas inlet to not materially above 40 C. at the gas outlet, in a manner compelling the condensate to gravitate through the region of highest temperature.

3. In the recovery of ammonia from producer gas subjecting an ascendingcurrent of producer gas prior to the removal of ammonia to temperatures progressively dimin ishing from not materially below S0O C. to not materially above 40 C. in a manner compelling the condensate to gravitate through the region of highest temperature and thereafter passing the cooled gas in contact With cold, ammonia-absorbing agents.

4. In the recovery of ammonia from producer gas'passing an ascending current of producer gas prior to the removal of ammonia in a plurality of streams in contact with extraneously cooled surfaces in such Way that the gas is subjected to progressively diminishing temperatures from not materially below 80 C. at the gas inlet to not materially above 40 C. at the gas outlet, in a manner'4 compelling the condensate to gravitate through the region of highest temperature and thereafter passing the cooled gas in contact with cold ammoniaabsorbing agents.

In testimony whereof We aix our signatures in presence of two Witnesses.

ARTHUR HENRY LYMN. NIELS EDWARD RAMBUSH. Witnesses:

R. DUNGERNSTERNBERG, DonoTHY MARY ABBOTT. 

